Fertility variation and effective number in the seed production areas of Pinus radiata and Pinus pinaster

Maritime (Pinus pinaster Ait.) and radiata (Pinus radiata D. Don.) pines are exotic species for Turkey. The afforestations of these species have been continued since late 1960s. There are approximately 54,000 and 1,700 hectares of industrial plantations, 333 and 81 hectares of seed stands of R pinaster and R radiata pines according to 1997's data from the forest inventory in Turkey, respectively. Production of female and male strobili was surveyed for two consecutive years in a seed stand of P. radiata, and a plantation of R pinaster in northern Turkey. There were positive and significant correlations (r = 0.406 and 0.709 in P radiatal 0.596 and 0.853 in R pinaster for consecutive two years) between female and male strobilus production. The effective numbers of parents were calculated as percentages of census number to 76% and 70% in the R radiata seed stand, and 83% and 78% in the R pinaster plantation for 2001 and 2002, respectively. Male fertility variation was larger than female fertility variation in R radiata for both years, but the variation of female fertility was larger than that of male fertility in P. pinaster. Management of the stands and procedure of seed collection were discussed.